Radio communications systems utilizing multiplexed noise codes are generally known, a typical example being shown and described in U.S. Pat. No. 4,293,953, entitled, "Bi-Orthogonal PCM Communications System Employing Multiplexed Noise Codes," which issued to Frank S. Gutleber, the present inventor, on Oct. 6, 1981.
The concept of code expansion for the general class of multiplexed noise codes comprised of code mate pairs having autocorrelation functions which upon detection provide an impulse is also generally known. One known expansion concept involves the butting of one code mate with the other code mate and is a technique disclosed, for example, in U.S. Pat. No. 3,461,451, entitled, "Code Generator To Produce Permutations Of Code Mates," which issued to the present inventor on Aug. 12, 1969.